The BBC published photos of around a dozen special forces soldiers on four vehicles heavily equipped with weaponsCredit:
BBC

The rebel unit, made up of former Syrian special forces who defected, was reportedly retrained by the British and Americans.

There have also been reports that British special forces inside Libya have destroyed Isil suicide vehicles in Misrata.

The deployment Britain's special forces does not require parliamentary approval, unlike the deployment of regular soldiers. The Ministry of Defence would not comment on the role of special forces.

The BBC said that the photos were taken immediately after an Isil attack had killed nine of the rebels at the southeastern Al Tanaf base.Credit:
BBC

In June First Lieutenant Mahmoud al-Saleh, a rebel commander, told The Times that he was being assisted by special forces.

“They helped us with logistics, like building defences to make the bunkers safe,” he said. “They [Isil] attack us at all times, 3am, 5am, 4pm, 11pm. If you look at the timing of the assaults it’s clear they don’t want us to get any rest. They’re using missiles, mortars and many suicide bombers."

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Isil seized al-Tanf, which occupies a critical location near the Iraqi and Jordanian borders, last year. In May an Isil armoured vehicle packed with explosives drove into the rebels' base and killed 11 members of the NSA, injuring 17 others.

The wounded were flown in American helicopters to Jordan. The suicide attack damaged the structure of the al-Tanf base, with British troops crossing from Jordan to help them to rebuild their defences.

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Since starting with a 2011 crackdown on anti-government protests, Syria's conflict has evolved into a complex, multi-front civil war that has left more than 280,000 dead and forced millions from their homes.

Isil emerged from the chaos in mid-2014, seizing control of large parts of the country and neighbouring Iraq, declaring a fundamentalist Islamic "caliphate" and committing widespread atrocities.

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In August 2013 David Cameron, the former Prime Minister, was defeated in the House of Commons when he failed to secure enough votes from MPs for airstrikes on Syria against the Assad regime. He won a subsequent vote in December last year.

A New Syrian Army's spokesman refused to comment on the pictures of the special forces but acknowledged that they are helping. He told the BBC: "We are receiving special forces training from our British and American partners. We're also getting weapons and equipment from the Pentagon as well as complete air support."

The NSA emerged from a $500 million Pentagon programme with aimed to create a well-trained rebel force to take on Isil. However the project was abandoned after the first trained unit sent into Syria was kidnapped by the al-Qaeda-affiliated Nusra Front. A second batch of trainees defected and gave their weapons away.